After Newt Gingrich's bravura performance in the final South Carolina debate and his drubbing of Mitt Romney on primary day, the former speaker's challenge in Monday night's debate in Tampa, Fla., was to maintain if not increase his momentum eight days before the Florida Republican presidential primary.

Meanwhile, Romney's challenge was to give his supporters who were shell-shocked by the Palmetto State results reasons to believe he had it in him to turn it around, to stand to do what needed to be done to beat Gingrich in Florida.

That said, neither Gingrich or Romney, the two candidates who appear to have a real chance at the nomination, fully met those challenges. Though they didn't appear to do anything to hurt themselves, they probably didn't do much to improve their respective standings in Florida, either.

Romney, true to his post-South Carolina promise that he would aggressively make sure to tell Florida Republicans of Gingrich's character defects as he sees them, delivered a scathing indictment of his rival, accusing him of leaving Congress in disgrace because of ethics issues only to become an influence-peddler and lobbyist.

Gingrich may have seized the initiative at the last debate by unloading on CNN's John King, the moderator. But it was Romney who seemed determined Monday night to dictate the terms of the evening by going after Gingrich. (Rep. Ron Paul and Rick Santorum were on the stage too, but, despite Santorum's rejection of the idea that it has become a two-person race, it really has.)

Whether he was just tired or not able to feed off the energy of an audience that was far more subdued than the audience in Charleston last week (and had been instructed to keep reaction to a minimum) Gingrich seemed more exasperated than anything else by Romney's fusillade of charges at the start of the debate.

Or maybe it was just his version of Muhammad Ali's rope-a-dope. Still, if you were scoring the debate up to the first commercial break like a boxing match, Romney would have been ahead on points.

If Gingrich was employing the rope-a-dope, he forgot the part about pummeling your opponent once he has punched himself out. Gingrich never really launched a sustained counterattack against Romney.

Instead, the debate settled into a more languid affair covering some of the topics one would expect in Florida — the space industry, the housing crisis, sugar subsidies and immigration and the related subject of English-only on official government forms.

It was difficult to discern many differences between the candidates at times. Indeed, on many issues, there aren't very many with the exception of Paul's positions on foreign policy which have been described by his critics, with some justification, as isolationist.

With the similarities between the candidates on issue positions, the contest may very well come down to personalities and which one voters sense to be the truest conservative.

To that end, moderator Brian Williams of NBC News asked a question meant to help Republican voters reach an answer, who had done the most for the conservative movement.

Gingrich and Romney's answers were telling because they encapsulated something of the problems facing the two men, the reasons why their many detractors loathe them.

Like Zelig, Gingrich basically placed himself at every important moment in the conservative movement going back to Barry Goldwater's 1964 Republican presidential campaign.

Romney said he had raised a family (does that make you a conservative?) run businesses (same question as before) and served as the Republican governor of Massachusetts, one of the nation's bluest states.

In short, one man's credentials seemed more than a little too padded and self-aggrandizing, the other's suspiciously, to conservative minds, of the country club Republican and, daresay, purple (Republican red and Democratic blue) variety.

And that helps explain why it's been so hard for so many Republican voters to choose this cycle. And if Monday night's debate is any guide, it seems like it may not get any easier.

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